Pop-up package assembly



FIG. 1 is a perspective view of a pop-up package assembly showing my new design;

FIG. 2 is another perspective view thereof;

FIG. 3 is another perspective view thereof; and,

FIG. 4 is another perspective view thereof, in a partially closed position.

The broken lines showing are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a pop-up package assembly, as shown and described. 